media: Support SetCdm() on VideoDecodeAccelerator interface.

media/video/video_decode_accelerator.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_
 #define MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 42 matching lines @@
   };
 
   // Interface for collaborating with picture interface to provide memory for
   // output picture and blitting them. These callbacks will not be made unless
   // Initialize() has returned successfully.
   // This interface is extended by the various layers that relay messages back
   // to the plugin, through the PPP_VideoDecoder_Dev interface the plugin
   // implements.
   class MEDIA_EXPORT Client {
    public:
+    // SetCdm completion callback to indicate whether the CDM is successfully
+    // attached to the decoder. The default implementation is a no-op since most
+    // VDAs don't support encrypted video.
+    virtual void NotifyCdmAttached(bool success);

[xhwang, 2015/11/13 01:16:55]

Moved up since this is part of the initialization process.

+
     // Callback to tell client how many and what size of buffers to provide.
     // Note that the actual count provided through AssignPictureBuffers() can be
     // larger than the value requested.
     virtual void ProvidePictureBuffers(uint32 requested_num_of_buffers,
                                        const gfx::Size& dimensions,
                                        uint32 texture_target) = 0;
 
     // Callback to dismiss picture buffer that was assigned earlier.
     virtual void DismissPictureBuffer(int32 picture_buffer_id) = 0;
 
@@ skipping 17 matching lines @@
 
    protected:
     virtual ~Client() {}
   };
 
   // Video decoder functions.
 
   // Initializes the video decoder with specific configuration.  Called once per
   // decoder construction.  This call is synchronous and returns true iff
   // initialization is successful.
+  //
+  // For encrpyted video, the decoder needs a CDM to be able to decode encrypted
+  // buffers. SetCdm() should be called after Initialize() to set such a CDM.
+  // Client::NotifyCdmAttached() will then be called to indicate whether the CDM
+  // is successfully attached to the decoder. Only when a CDM is successfully
+  // attached can we start to decode.
+  //
   // Parameters:
   //  |profile| is the video stream's format profile.
-  //  |client| is the client of this video decoder.  The provided pointer must
-  //  be valid until Destroy() is called.
+  //  |client| is the client of this video decoder. Does not take ownership of
+  //  |client| which must be valid until Destroy() is called.
   virtual bool Initialize(VideoCodecProfile profile, Client* client) = 0;
 
+  // Sets a CDM to be used by the decoder to decode encrypted buffers.
+  // Client::NotifyCdmAttached() will then be called to indicate whether the CDM
+  // is successfully attached to the decoder. The default implementation is a
+  // no-op since most VDAs don't support encrypted video.
+  virtual void SetCdm(int cdm_id);
+
   // Decodes given bitstream buffer that contains at most one frame.  Once
   // decoder is done with processing |bitstream_buffer| it will call
   // NotifyEndOfBitstreamBuffer() with the bitstream buffer id.
   // Parameters:
   //  |bitstream_buffer| is the input bitstream that is sent for decoding.
   virtual void Decode(const BitstreamBuffer& bitstream_buffer) = 0;
 
   // Assigns a set of texture-backed picture buffers to the video decoder.
   //
   // Ownership of each picture buffer remains with the client, but the client
@@ skipping 65 matching lines @@
 // uses "Destroy()" instead of trying to use the destructor.
 template <>
 struct MEDIA_EXPORT DefaultDeleter<media::VideoDecodeAccelerator> {
  public:
   void operator()(void* video_decode_accelerator) const;
 };
 
 }  // namespace base
 
 #endif  // MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_